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Electricians - hard wiring my generator into my breaker box


Nitrousbird

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I have an all-electric home (5 ton heat pump, electric water heat, etc.). My wife really wanted a generator, and we found a good deal on a 3250 watt unit (4000 watt max) unit that is supposed to put out what they say it does according to a lot of positive reviews.

 

Anyway, everything online is transfer switch this, transfer switch that. Ummm, can't I just shut off the main breaker to the house before firing up the generator? Most of my neighbors have propane + full house generators, so it's usually pretty easy to tell when the electric comes back on. I'm not some idiot that would forget about the breaker, and would be the only one using it.

 

I know I'd have to switch off the hot water heater, and I am doubting the furnace/heat pump will be able to run off of this, but I want to at least run the other essentials.

 

So what would be the best suggested way to wire this? I was thinking a line to the breaker box, a receptacle, then a male to male jumper line from that receptacle to the generator. Any suggestions, guidance? If this is a good method, would I be able to safely back-feed a breaker, so that when it's not being used for a generator, I could use that outlet as a 240v outlet?

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I work in the industry, and I agree with the following recommendation:

 

The only recommended method to connect a generator to house wiring is by having a qualified electrician install a power transfer switch. This switch must be installed in accordance with the National Electrical Code® (NEC), which is published by the National Fire Protection Association, and all applicable state and local electrical codes. Call a qualified electrician or check with your utility company to see if they can install the appropriate equipment.

 

All of my customers use an ATS.

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The transfer switch is a good idea, from the "not Killing an AEP employee" standpoint. Plus, feeding electricity onto the grid without AEP's approval can cause hefty fines (Like $50,000). I realize you would never, not forget to close the breaker, but someone else might be home when the power is out.
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I've done a few installs on the cheap where I just backfed a breaker in the panel, all hardwired. This isn't the "correct" way to do it, but it works just fine so long as both breakers aren't on at the same time. If I was doing this to my own house this is how my cheap ass would do it, but I know that I'd be the only one using it too.
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IMO, A 3200W Generator isn't going to go very far.

If I was going to go through the trouble of hard wiring it with a transfer, I'd get something that could support me comfortably during an extended outage.

 

I run an 8K during power outages to ensure heat, sumps, refrigerator, and some entertainment. That still isn't nearly enough once you factor in water heaters, ect.

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IMO, A 3200W Generator isn't going to go very far.

If I was going to go through the trouble of hard wiring it with a transfer, I'd get something that could support me comfortably during an extended outage.

 

I run an 8K during power outages to ensure heat, sumps, refrigerator, and some entertainment. That still isn't nearly enough once you factor in water heaters, ect.

 

 

This...

 

:thumbup:

 

KillJoy

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#1: A transfer switch is almost as much as the freaking generator

 

#2: I don't exactly follow every letter of the law

 

#3: I only live with my wife. If the power was out when my wife was home, she isn't going to be rolling a generator that weighs more than she does outside, connecting a line, getting it started, etc. I don't think she has ever pull started an engine in her life.

 

#4: Not only do I know better than to not flip the breakers, I will also post multiple safety checklists (one by the socket, one on the generator, and one by the breaker panel) to 100% ensure I NEVER, EVER FORGET. I'd also keep the other breaker off when not in use, just to be extra safe.

 

So Scott has done what I'm am talking about. I assume backfeeding the breaker worked without any issues?

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IMO, A 3200W Generator isn't going to go very far.

If I was going to go through the trouble of hard wiring it with a transfer, I'd get something that could support me comfortably during an extended outage.

 

I run an 8K during power outages to ensure heat, sumps, refrigerator, and some entertainment. That still isn't nearly enough once you factor in water heaters, ect.

Exactly. I just want to make sure food doesn't spoil, my sump gets power if needed (though I think I am going to go w/ a backup pump and battery backup for that anyway), and maybe run an electric portable heater if needed in the winter...this isn't for multi-day power outages.

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#1: A transfer switch is almost as much as the freaking generator

 

#2: I don't exactly follow every letter of the law

 

#3: I only live with my wife. If the power was out when my wife was home, she isn't going to be rolling a generator that weighs more than she does outside, connecting a line, getting it started, etc. I don't think she has ever pull started an engine in her life.

 

#4: Not only do I know better than to not flip the breakers, I will also post multiple safety checklists (one by the socket, one on the generator, and one by the breaker panel) to 100% ensure I NEVER, EVER FORGET. I'd also keep the other breaker off when not in use, just to be extra safe.

 

So Scott has done what I'm am talking about. I assume backfeeding the breaker worked without any issues?

Yes I have, and yes as long as it is done correctly.

Whats the wattage on an whole house generator somewhere in the neighborhood of 20kw? Is that 20,000 watts? And you are considering hooking up a 3250 watt generator? What would happen if you forgot to turn the other breaker off?

 

What would happen, wouldn't be anything until you either overloaded the generator or the power came back on, then it would get dangerous real quick.

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The best thing to do if you're not going to use a transfer switch is to actually unhook your main feed coming into the main panel during generator use. This will insure no mistakes with backfeeding

 

People do this all of the time with no problems...Its what I would do...

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I may want to come over and take a look at yours in the next couple of weeks. I'll be in Reynoldsburg a decent amount for the next few weeks prepping the R-burg house for sale

 

30 amp breaker ,10 gauge wire , 1 220 20 amp plug good to go . thats the way i have mine and mine is a 3500 watt one and will run all the lights tvs refrieg but no 220 stuff .

Sounds like a plan...I'll have to shop around at Home Depot this weekend and see what they have. I have plenty of space in my breaker setup.

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I would say if your wife is ever going to be doing it then I would go transfer switch. Being all electric is what's killing you......hot water heater, furnace, and things like that eat a ton of energy. That's just not going to run very much for you.....think if the power goes down in the winter time which is when it's more important really to have one. I run a 5500 here and I'm not all electric but I can also run my entire house including my well pump on that although I never do.

I just backfeed mine through the dryer breaker. I use the 220 side of the generator with a 4 wire cord and send 1 wire down each leg of the breaker. Definitely not the smart way or correct way to do it but it's worked fine the 2 times I've had to do it in 8 years. Just kill the main disconnect and fire the generator up.

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If you're too cheap to use a proper transfer switch, *some* localities allow the use of a double-pole knife switch (aka the thing your friendly neighborhood mad scientist throws before shocking the corpse and screaming "it's alive!"). Mind you I said *some*, so again, check with a properly qualified residential electrician before doing this.
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If you have a Square D box they make an interlock plate that will allow you to safely backfeed the panel and it does comply to the NEC. This is how I wired my house. Total material will run you about $150 to do it correctly. If you need help let me know.

 

http://www.interlockkit.com/

 

That site will give you an idea of what I am talking about. It is cheapest to get the interrupt through Grainger

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If you have a Square D box they make an interlock plate that will allow you to safely backfeed the panel and it does comply to the NEC. This is how I wired my house. Total material will run you about $150 to do it correctly. If you need help let me know.

 

http://www.interlockkit.com/

 

That site will give you an idea of what I am talking about. It is cheapest to get the interrupt through Grainger

 

pretty slick idea.....that doesn't look that hard to make either.

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If you have a Square D box they make an interlock plate that will allow you to safely backfeed the panel and it does comply to the NEC. This is how I wired my house. Total material will run you about $150 to do it correctly. If you need help let me know.

 

http://www.interlockkit.com/

 

That site will give you an idea of what I am talking about. It is cheapest to get the interrupt through Grainger

 

Not for me. :)

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